It'll be done when it's done. 
That said, game mechanic stuff is trivial compared to the engine work.
In GalCiv II, I routinely made dramatic changes to the AI or economy or what have you in-between updates (as some long time GalCiv players know).
For instance, we could implement one combat system, decide we don't like it, and do a different one in the next week -- as long as the actual mechanics don't make their way into the engine. Hence, the ugly looking beta. 